Acute steroid myopathy. An AIDS patient taking zidovudine complains of myalgia and weakness

Myopathy in medicine is represented by a group of diseases, which are based on metabolic disorders in muscle tissues (most often in skeletal muscles). In the process of development, muscles completely or partially lose their functionality (weaken or lose mobility), and in combination with metabolic disorders, all this leads to thinning muscle tissue and deprives the patient of the opportunity to carry out the usual active life.

Most often, the development of pathology begins in childhood, but for non-genetic reasons, the development of myopathy is also possible in adulthood. It is important to understand that this is a disease that is associated with metabolic disorders. Therefore, if there were precedents in the family, it is necessary to be examined in a timely manner and monitor the condition of the muscles.

Let's designate the main symptoms that are characteristic for the development of pathology:

• Muscle weakness becomes permanent, it does not go away even after rest;
• Muscles become inactive, immobile, this can concern both a group of muscles and individual areas on the body. In most cases, myopathy affects the lower or upper limbs, as well as the muscles of the pelvis or shoulder girdle;
• Muscle tone decreases - they become lethargic and flabby;
• Curvature of the spinal column due to the weakness of the muscular frame and their inability to maintain the body in the correct position. Most often, with myopathy, there is a curvature of the spine to the side (scoliosis) or backward (kyphosis);
• Pseudo hypertrophy - thinning of the affected limbs provokes the development of an increase in other parts of the body due to the growth of adipose and connective tissue.

Types of myopathy

The term "myopathy" comes from Greek, where "myo" is muscle, and "pathos" is suffering. Literally translated, pathology is characterized by the suffering and pain of muscle tissue. Myopathy is a broad group of diseases that are combined common features growing muscle weakness in various fields trunk, a decrease in its tone and basic reflexes, as well as gradual atrophy.

Depending on the age category the patient, as well as the reasons for the transformation of muscle groups, the pathology is divided into several varieties:

1. - an increase in muscle size due to the growth of adipose tissue, in as a result, they become large, but weak. This form pathology is the most malignant of all existing, as it progresses rapidly and has severe consequences. Most patients with Duchenne myopathy remain disabled or die due to the immediate development of cardiac and respiratory failure. It is important to note that this form of pathology develops already in the first years of life, affecting mainly boys.
2. Erba Rota - hereditary form pathology, which often develops in patients after 20 years of age. There is a transformation of the pelvic muscles, which subsequently "transfers" to the shoulder girdle. Often there are signs of hyperlordosis (curvature spinal column forward as a result of atrophy of the muscle groups of the back and abdomen). Violated facial expressions due to muscle deformation. The lips protrude, the patient loses the ability to smile. There is a change in gait.
3. Becker's myopathy- Pathology affects the muscles of the lower extremities. The onset of the disease is characterized by an increase calf muscles, then atrophy extends to the area of ​​the hip girdle. If at the beginning of the development of the pathology the patient can still move, then with the progression of Becker's myopathy, he loses this ability. In most cases, this form of pathology is accompanied by heart failure.
4. Landouzy Dejerine- Pathology develops in adolescence. First, atrophy of the muscles of the face begins - the patient's facial expressions are difficult, the lips turn out, the eyelids do not open, the face becomes immobilized. Later, atrophy "falls" on the area of ​​the shoulder girdle, but the patient is still long time maintains normal performance.
5. Steroid myopathy- the presence of proximal ability and muscle wasting, the symptoms of pathology are more pronounced in the upper limbs. This form of pathology is classified as metabolic myopathy (the disease develops due to a hereditary or acquired metabolic disorder).
6. Myopathy of the eyes - there is a decrease in mobility eyeballs with preservation or partial defeat visual function, in some cases retinal pigmentation is observed. There are 2 types of eye myopathy - ocular and oculo-pharyngeal (simultaneous damage to the muscles of the eyes and pharynx occurs).
7. Inflammatory myopathy- occurs as a complication infectious diseases. Inflammatory agents penetrate the skeletal muscles and damage tissues. Symptoms of pathology - pain in the body, general weakness, swelling, decreased activity.

There are other forms of myopathy.

Diagnostics

Hereditary myopathy is not amenable to complete cure Therefore, the main methods of therapy are aimed at maintaining the health of the patient. Timely diagnosis pathology improves the quality of life of the patient.

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Diagnostic methods for suspected myopathy:

• general and biochemical blood test;
• muscle fiber biopsy;
• electromyogram;
• molecular genetic analysis (in some cases).

Treatment

Medicine has not developed methods that allow you to completely cure myopathy, so the treatment of pathology is based on the elimination of its symptoms.

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Main medications for the treatment of muscular dystrophy are anabolic hormones. For supporting defensive forces body, the patient is prescribed a complex of vitamin and minerals.

Additionally, with myopathy, it is shown:

1. Orthopedic correction - the use of special devices that help the patient walk independently (wheelchairs, orthoses).
2. Breathing exercises - complex special exercises helps to improve ventilation of the lungs, which reduces the risk of developing pneumonia.
3. Therapeutic gymnastics - moderately active gymnastics helps muscles maintain motor activity, it slows down the process of muscle atrophy.
4. Proper nutrition - balanced diet helps support immunity.
5. Swimming in the pool.

All of these procedures are prescribed to patients to alleviate general condition and slowing down the process of muscle degradation, but they do not have any effect on the course of the pathology.

Complications

As muscle weakness progresses, the following may develop:

• violation of the functionality of the respiratory system (insufficiency) (with atrophy of the muscles of the respiratory system);
• loss of motor activity;
• congestive pneumonia - due to a sufficiently long inactivity of the patient, the risk of congestion is likely, which leads to the development of an inflammatory process;
• increased risk of premature lethal outcome.

Prevention

Holding effective prevention congenital myopathy is carried out in those families where cases of development have already been observed similar pathology. The basis preventive method included medical genetic counseling of spouses with a real risk assessment of the birth of a newborn with a pathology.

Facial-shoulder-shoulder myodystrophy. Recommended physiotherapy. Foot drop can be treated with orthopedic correction methods. For patients with the impossibility of independent movement, special motorized wheelchairs with adjustment for the patient's height are needed. Wearing a corset can prevent the development of gross lordosis with protrusion of the abdomen.

With oculopharyngeal myodystrophy to fight ptosis mild degree patients are advised to wear specially designed glasses. In more severe cases, blepharoplasty is used with excision of the muscle that lifts the eyelid. Cricopharyngeal myotomy is a way to deal with severe dysphagia.

Features of the treatment of limb-girdle myopathies discussed in detail in our article.
With myotonic dystrophy phenytoin is used at a dose of 100 mg 3 times a day orally. However, the indication for its appointment is only severe myotonia, which violates normal life sick. Quinine sulfate and procainamide are prescribed with great care, because they can affect heart function (often there is an elongation P-R interval). Usually patients with myotonic dystrophy do not complain of myotonia.

The main goal of treatment is the prevention and control of concomitant systemic manifestations.

Metabolic myopathies

Metabolic myopathies is a large, heterogeneous group of hereditary and acquired disorders, which are based on metabolic disorders. This section discusses endocrine myopathies, malignant hyperthermia, acid maltase deficiency, McArdle disease, and carnitine-O-palmityltransferase deficiency. A. Course of the disease, prognosis and treatment

1. Endocrine myopathies
Thyrotoxic myopathy. The main symptom is weakness and mild muscle wasting. Pathological fatigue and heat intolerance also occur. Involvement of the bulbar musculature and respiratory muscles may be observed. Differential diagnosis should be made with hypokalemic periodic paralysis and myasthenia gravis due to hyperthyroidism. Treatment is based on the correction of the hyperthyroid state.

Also, the patient's condition may relieve beta-blockers. With severe hyperfunction thyroid gland prescribe glucocorticoids, which block the peripheral conversion of thyroxine to triiodothyronine.

With hypothyroid myopathy pseudohypertrophy of muscles, weakness, painful muscle cramps, muscle swelling and rapid fading of reflexes. Women are more susceptible to the disease. There may be rhabdomyolysis or involvement of the respiratory muscles. Serum creatine kinase levels may be elevated. The diagnosis is confirmed by the results of thyroid function tests. Treatment is aimed at achieving a euthyroid state.

Steroid myopathy characterized by the presence of proximal weakness and muscle wasting, more pronounced in the upper limbs. Patients have difficulty climbing stairs. Creatine kinase levels are normal. In iatrogenic steroid myopathy, symptoms regress after cessation of steroid treatment. Soluble steroid drugs eg dexamethasone and triamcinolone are more likely to cause myopathy. EMG reveals normal activity and the absence of spontaneous activity.

Treatment includes reducing the dose of steroids to the minimum therapeutic level, switching to insoluble steroids, or treatment for alternative scheme. Improvement is usually not immediate and may take several months. Recovery is promoted by a properly selected diet and exercise.

2. Malignant hyperthermia- this is serious condition, which is observed during general anesthesia and is characterized rapid rise body temperature due to an uncontrolled, rapid increase in skeletal muscle metabolism with rhabdomyolysis. Mortality in malignant hyperthermia syndrome is high. This syndrome is a consequence of autosomal dominant intolerance to general anesthesia, in particular with the use of halothane or succinylcholine. Body temperature rises to 43°C, marked metabolic acidosis, tachycardia, muscle rigidity, disseminated intravascular coagulation, coma, areflexia, and death are noted.

Significantly increased level creatine kinase» sometimes up to 10,000 times normal performance. Also characteristic are myoglobinuria, increased levels of various muscle enzymes, and the release of potassium from muscle cells.

Most prognosis cases are disappointing. The likelihood of death can only be reduced with early recognition of the syndrome and prompt treatment. The pathogenesis is based on dysfunction calcium channels sarcoplasmic reticulum (ryanodine receptors). Pathology of ryanodine receptors can enhance the release of calcium. The gene responsible for the normal function of ryanidine receptors is located on chromosome 19 (13-1). Malignant hyperthermia can be observed in combination with dystrophinopathies and congenital myopathy (central rod disease).

Malignant neuroleptic syndrome(ZNS) also manifests high temperature, muscle rigidity, tachycardia and rhabdomyolysis. However, unlike malignant hyperthermia, it develops much more slowly - within days or weeks" is not familial and usually begins after taking drugs that block central dopaminergic pathways, such as phenothiazines, lithium, haloperidol, or after stopping levodopa drugs. in Parkinson's disease.

Prevention of NMS lies in early diagnosis developing malignant hyperthermia, when the symptoms are still localized, for example, isolated trismus is observed. Anesthesiologists should be familiar with neuroleptic malignant syndrome and use dantrolene, which significantly reduces disability and mortality due to NMS. Barbiturates, nitrous oxide, opiate-non-depolarizing relaxants used for anesthesia do not cause malignant hyperthermia.

Treatment of malignant hyperthermia depends on the severity, which, in turn, is determined by the dose and duration of the patient's stay under anesthesia. In mild cases, only the termination of anesthesia is sufficient. In more severe cases, correction of the violation should be carried out immediately. acid-base balance to save the patient's life. Need to strengthen artificial ventilation lung and start intravenous sodium bicarbonate (2-4 mg/kg). It is recommended to wrap with cold sheets and intravenous administration of chilled solutions until the body temperature drops to 38 ° C.

Introduction of fluids and the appointment of diuretics is necessary in the presence of myoglobinuria. Recommended for acute stress response steroid hormones. Dantrolene is a specific therapy because it reduces the release of calcium from the sarcoplasmic reticulum. It is administered intravenously at a dose of 2 mg/kg every 5 minutes up to 10 mg/kg. It contributes to the correction of concomitant hyperkalemia. Calcium should not be prescribed to combat hyperkalemia.

Congenital myopathies usually manifest in infancy sluggish baby syndrome with poor muscle strength. The content of creatine kinase in plasma is normal, and the EMG has a myopathic type. Central rod disease usually presents with mild, non-progressive muscle weakness in the neonatal period, resulting in delayed walking and other indicators. physical development. This disease is inherited in an autosomal dominant manner. Non-crimson myopathy (congenital non-progressive myopathy, filamentous myopathy) is a more severe disease, manifested by muscle weakness and hypotension. The consequence of the disease is difficulty in feeding, walking delay and sometimes weakness of the respiratory muscles. The disease progresses slowly; older children or adults with this myopathy are characterized by a decrease muscle mass and an abnormally long face with a protruding lower jaw. Non-crimson myopathy is inherited either in a dominant or recessive manner. Centronuclear (myotubular) myopathy again manifests in the neonatal period. Defeat is characteristic oculomotor muscles.

Muscular dystrophies

The onset and severity of the disease varies. Specific diagnostic tools are available for the diagnosis of many of these diseases. genetic tests and all patients/families should be genetic counseling. The onset of diseases is usually childhood, although some forms appear later. Distinguish the following, often found muscular dystrophies.

Myotonic dystrophy

This is the most common hereditary disease muscles. Myotonic dystrophy type 1 is inherited in an autosomal dominant manner, occurs due to the expansion of trinucleotide repeats of cytosine-thymine-guanine (CTG) in the 3"-untranslated region of the gene encoding muscle protein kinase (DMPK), located on chromosome 19q13.3. In addition to myopathy disorders of consciousness, subcapsular cataracts, cardiac conduction disorders, sensorineural hearing loss, frontal alopecia, and hypogonadism.Myotonic dystrophy type 2 is also an autosomal dominant disease, due to the expansion of cytosine-cytosine-thymine-guanine (CCTG) nucleotide repeats. ) in intron 1 of the ZNF9 gene located on chromosome 3q. It causes a proximal muscular type of dystrophy, sometimes with pain and hypertrophy, but without impaired consciousness. Myotonic dystrophy types 1 and 2 leads to alternative splicing of the voltage-gated chloride channel ( C1C-1) and is therefore considered together with channelopathies.

Duchenne muscular dystrophy

It is an X-linked disorder and therefore affects boys; associated with a deletion of the dystrophin gene. Usually manifests itself at the age of 2-6 years. As a rule, the patient from an early adolescence chained to wheelchair. Patients in the majority do not live up to 20 years. Duchenne muscular dystrophy is characterized by weakness of the proximal muscle groups and muscles of the lower and upper limbs, pseudohypertrophy of the gastrocnemius muscles, cardiac conduction disorders and scoliosis are possible.

Becker muscular dystrophy

It is also an X-linked disorder with a distribution of muscle weakness similar to Duchenne muscular dystrophy (considered a variant of Duchenne muscular dystrophy). It is usually milder than Duchenne myopathy, but the severity can vary. Symptoms may not occur until 10 years or later, patients may have a long lifespan, albeit with varying degrees disability.

Amery-Dreyfus muscular dystrophy

An X-linked disease associated with a mutation in the emerin gene. The disease manifests itself at the age of about 5 years with weakness of the muscles of the upper and lower extremities. Weakness of the proximal muscle group develops later. Perhaps the development of contractures and movement disorders in the joints; patients are at risk for sudden cardiac death due to conduction disorders.

Pelvic-brachial muscular dystrophy of Leiden-Möbius

Both dominant (type I) and recessive (type II) types of inheritance are possible. Several gene abnormalities can cause this syndrome so the prognosis is variable. Cardiac disorders may appear. Boys and girls get sick with the same frequency; symptoms usually appear in late childhood.

Shoulderoscapular-facial muscular dystrophy of Landouzy-Dejerine

It is an autosomal dominant disorder that affects both males and females. The debut usually occurs in late childhood or early adulthood. Symptoms may be mild, although generalization is possible; lower limbs hit later.

Channelopathies are a recently identified group of diseases in which there is a defect in the genes of one of the ion channels involved in the regulation of normal muscle tissue. Myotonia is caused by repetitive bursts of action potential when muscle contraction is activated spontaneously. As a result, it becomes impossible to relax the muscle. Symptoms usually improve with physical activity. Conversely, paramyotonia worsens in the cold and after exercise. exercise. Becker's disease is the most common form, while Thomsen's disease, although less common, is usually characterized by more easy flow. Hyperkalemic periodic paralysis can be triggered by potassium intake, and glucose can relieve the symptoms of this disease. The reverse applies to hypokalemic periodic paralysis. Andersen's syndrome is an autosomal dominant disorder in which paralysis attacks are provoked by prolonged inactivity (including sleep), caloric insufficiency, and cold. It is accompanied by an extension interval Q-G on the electrocardiogram, a tendency to tachycardia. Malignant hyperthermia can be triggered by vapor anesthetics, depolarizing muscle relaxants, or excessive physical activity. Sustained increase in the concentration of intracellular calcium in skeletal muscle leads to excessive muscle contraction with hyperthermia, metabolic acidosis, hypoxia and hyperkalemia.

Increasingly in clinical practice reveal mitochondrial myopathies, but they still belong to rare diseases.

• MELAS syndrome - episodic encephalopathy, stroke-like episodes; progressive neurodegenerative disease, in many cases also causes diabetes mellitus.
• MERRF syndrome - atrophy optic nerve, peripheral neuropathy, dementia, myoclonic epilepsy, cerebellar ataxia and sensorineural hearing loss.
• Kearns-Sayre syndrome - progressive symptoms of damage to the oculomotor muscles, including ptosis, retinitis pigmentosa, sensorineural hearing loss, proximal myopathy, and cardiac conduction disturbances.
• CPEO syndrome (chronic progressive external ophthalmoplegia) is similar to Kearns-Sayre syndrome but has a later onset and is not accompanied by retinal degeneration.

Congenital metabolic diseases should be considered in the differential diagnosis of muscle lesions, especially when they occur in early age or when there is an appropriate family history. Differential Diagnosis includes glycogenoses. The diseases listed below are clinical picture which are primarily muscular symptoms.

• Pompe disease (type II glycogenosis) occurs due to a deficiency of the lysosomal enzyme α-1,4-glucosidase (acid maltase), which leads to an unregulated accumulation of glycogen with impaired muscle structure and function.
• Cori's disease (glycogenosis III type; limitdextrinosis) occurs due to a deficiency of amyl-1,6-glucosidase, leading to the accumulation of abnormal glycogen that cannot be broken down to release glucose.
• McArdle's disease (type V glycogenosis) occurs due to myophosphorylase deficiency, which also leads to impaired glycogen breakdown. There is swelling and tenderness of muscle tissue, creatine kinase concentrations are generally very high, and there may be episodes of rhabdomyolysis.
• Tarui disease (glycogenosis type VII) leads to clinical manifestations similar to McArdle's disease and is associated with a deficiency of muscle phosphofructokinase.
• Deficiency of carnitine palmitoyl transferase causes episodes of muscle pain and weakness, periodic increase creatine kinase concentrations and myoglobinuria.

In clinics for adults, in addition to highly specialized centers, acquired muscle diseases are much more common than congenital ones. Among them, myopathy caused by alcohol abuse or medicines including glucocorticoids.

Acute alcoholic myopathy is relatively rare and leads to muscle necrosis, varying in volume. inflammatory infiltrate causes muscle weakness and muscle pain. Plasma creatine kinase levels are markedly elevated, and in this disease there may be myoglobinuria and rhabdomyolysis with concomitant kidney failure. Recovery in most cases occurs after the cessation of alcohol consumption and the use of supportive measures. Chronic alcoholic myopathy affects predominantly type II fibers (fast twitch, anaerobic, glycolytic). Classically, acute alcoholic myopathy occurs after 10 years of daily alcohol consumption in excess of 100 g (10-12 units) in terms of ethanol. The etiology is not exactly known. Factors include ethanol induction of mitochondrial dysfunction, which in turn leads to impaired ATP production and utilization. fatty acids; accumulation of acetaldehyde protein synthesis; impaired protein synthesis due to reduced amino acid availability and growth hormone/IGF-1 activity; education free radicals causes damage to cell membranes.

Steroid myopathy does not always occur with long-term use high doses glucocorticoids. It often develops when taking strong fluorinated glucocorticoids (dexamethasone, betamethasone and triamcinolone). As with alcoholic myopathy, there are acute and chronic forms. Acute steroid myopathy usually occurs after acute impact high doses of glucocorticoids and may take many months to recover. A subacute, necrotizing form of myopathy has been described when taking glucocorticoids, it is characterized by severe symptoms, the concentration of creatine kinase exceeds the norm by more than 10 times. The effect of glucocorticoids on myocytes disrupts protein synthesis and leads to loss of the protective effects of IGF-1. Furthermore, increased activity cellular protease increases the breakdown of muscle proteins. Biopsy reveals a variety of fiber sizes, loss of type II fibers, and necrotic and basophilic fibers throughout the muscle. As with other metabolic myopathies, the proximal muscles are usually affected, although in severe cases there may be more generalized involvement, including respiratory muscles. In patients treated with glucocorticoids for a long time, there are usually other clinical manifestations excess glucocorticoids at the time of myopathy. Treatment consists of minimizing exposure to glucocorticoids by reducing the dose, using topical formulations, taking the drug every other day, and avoiding fluorinated glucocorticoids. Doing resistance-enhanced exercise is beneficial in recovery normal function muscles and muscle mass. Recovery in chronic cases is slow, full recovery may not be.

A fully developed form of acute myopathy with tetraparesis is rare. For this disease characterized by an acute onset with generalized weakness. It is similar to steroid myopathy but has a more severe and more generalized course. Muscle relaxants also play a role in etiology.

EMG shows low or normal action potentials. Biopsy may reveal type II fiber atrophy or necrosis, similar to steroid myopathy. specific treatment does not exist. Recovery is usually complete, but may be prolonged.

Latest Research Results

Critical myopathy is accompanied by a lengthening of hospital stays, an increased risk of needing mechanical ventilation, and increased mortality. Patients are in a group increased risk developing critically ill myopathy if they have sepsis, hyperglycemia, or if they require glucocorticoid treatment. Among etiological factors distinguish between systemic inflammation (especially in sepsis), increased proteolysis, oxidative and metabolic stress. Neurological symptoms often develop and there are violations of the electromechanical interface. Intensive insulin therapy is recognized as a measure to protect patients from the consequences of critically ill myopathy.

Loss of muscle mass in adynamia is increased when combined with stress, and it is believed that this is due to hypercortisolemia. Essential amino acids, combined to reproduce the ratio found in muscle tissue, serve as a strong anabolic stimulus in myopathy due to weakness or the use of glucocorticoids. It is worth paying attention to the nutrition of patients receiving glucocorticoids who are in critical condition, and patients who are likely to be immobilized for a long time.

The addition of creatine increases physical abilities, violation of which is observed when glucocorticoids are administered to experimental animals in doses exceeding physiological ones. The supplement reduces the loss of muscle mass when taking glucocorticoids. Required clinical researches patients taking glucocorticoids or in the intensive care unit to study this drug, the appointment of which may become a safe prophylactic method.

Steroid myopathy is diagnosed when other causes of muscle weakness and atrophy are excluded. Other than the acute necrotizing form of steroid myopathy, there is usually no activation systemic inflammation or elevation of circulating muscle markers. To prevent the patient from developing myopathy, the dose of glucocorticoid should not be high, and the duration of administration should be long. For final diagnosis a muscle biopsy may be required. The prognosis varies and is related to the severity of the disease. Improvement usually occurs if glucocorticoid intake is reduced or discontinued. If possible, other risk factors for muscle loss should be excluded. They include certain drugs and alcohol abuse. There is no specific treatment. It is recommended to perform physical exercises with resistance to restore muscle mass and use food additives, but RCTs proving their effectiveness are not yet available.

Translation: Alexandra Varshal (translation is given with structural rearrangements and abbreviations)

Adapted from Khan and Larson: Acute myopathy secondary to oral steroid therapy in a 49-year-old man: a case report. Journal of Medical Case Reports 2011 5:82.

In 1932, Cushing described myopathy as one of the symptoms of hypercortisolism. Corticosteroids have entered medical practice in 1948 and in 1958 Dubois described the first patient with corticosteroid-induced iatrogenic myopathy. Since corticosteroids have become widely used in practice, clinicians often face acute and chronic forms steroid myopathy. Chronic steroid myopathy developing against the background of long-term use steroids is more common. Acute steroid myopathy (ASM) is less common and develops early in treatment, usually with intravenous administration high doses of steroids.

The first cases of ACM were described in asthmatics treated with intravenous corticosteroids in high dosage about status asthmaticus. MacFarlane and Rosenthal reported on a patient treated with intravenous hydrocortisone in whom ACM manifested as difficulty in coming off a ventilator. About the OSM that arises when oral intake steroids have been reported rarely. Kumar described a patient who developed myopathy after a single dose of a corticosteroid. We present a similar case in which a patient developed acute myopathy after two doses of methylprednisolone.

Disease history

A 49-year-old man presented to an orthopedic clinic with complaints of pain in the area of ​​the plantar surface of the foot. He was diagnosed plantar fasciitis and methylprednisolone was prescribed. On the second day of therapy, he experienced vague pain in the neck. He ignored her at first, but the pain intensified and became more widespread.

On the third day of treatment, myalgia and muscle weakness seized the muscles of the shoulder and thigh, and the patient stopped taking the medicine. He was examined by a physician on the fourth day of treatment: the pain and muscle weakness had progressed and spread more and more. The patient reported that he was unable to open the car door due to muscle weakness and arm pain. The muscles were painful on palpation, and the pain did not decrease even with the use of paracetamol - 500 mg every 6 hours. He had no fever, shortness of breath, flu-like symptoms, facial weakness, difficulty swallowing, or urinary or GI symptoms. She had only a history of gastroesophageal reflux disease.

On examination: BP - 130/85 mm Hg, pulse - 80 beats per minute, respiratory rate - 15 per minute, body temperature - 37.2 ° C, blood oxygen saturation 98% (normal: 96-98%). The muscles of the arm, including the small muscles of the hand, are painful on palpation. Sensitivity of the cranial and peripheral nerves preserved and symmetrical. The muscle strength of the shoulder and forearm is significantly reduced: 2 points out of 5. The tone of the facial muscles is normal. The patient's handshake was weak and he had difficulty getting up from a sitting position. The gait did not change, deep tendon reflexes were not affected, Babinski's sign was negative. cardiovascular, respiratory system and a stomach at survey - without features.

Test results: UAC and main biochemical indicators- without deviations from the norm. AT biochemical analysis blood, a significant increase in the level of CPK was noted - 891 U / l (norm - 22-198 U / l) and C-reactive protein - 14.86 mg / l (norm<5 mg/L). Незначительно повышены АСТ - 64 МЕд/л (норма 10-40 МЕд/л) и АЛТ - 69 МЕд/л (норма 9-60 МЕд/л). Биопсия мышц и электромиография не проводились.

Treatment

The patient was prescribed 400 mg ibuprofen every 6 hours, as usual for myalgias, and reexamined a week later. Seven days later, during a routine examination, the patient noted that his state of health had improved significantly: muscle pain had decreased and muscle strength had returned. On examination, the tone in all muscle groups was 5 points out of 5. A repeated biochemical blood test revealed that CPK and AST decreased to normal, while ALT remained slightly elevated (82 IU/l). Myoglobin in urine is negative.

The doctor met with the patient again 30 days after the onset of the disease. The patient felt well, returned to his usual way of life, agricultural work. The pain in the leg persisted, becoming worse with physical activity. On this occasion, the patient continued to take ibuprofen at a dosage of 400 mg as needed.

Discussion

OSM is a rare pathology and its pathogenesis is unclear. There are several theories, one of which is that corticosteroids activate a ubiquitin-dependent proteolytic system that attacks muscle cells. Another model suggests that insulin-like growth factor-1 (IGF-1), which prevents cell apoptosis, is inhibited by steroids, leading to increased apoptosis in muscle cells.

Askari et al. recorded ACM in six of nine patients treated with prednisolone per os from July 1972 to November 1973. In one of the patients, ACM began a few days after the start of treatment. Five patients received maintenance doses (15-60 mg) for 60-240 days without any signs of myopathy. However, four of these five patients experienced symptoms of corticosteroid myopathy when the maintenance dose was increased. The investigators concluded that the development of myopathy in patients receiving corticosteroids was independent of the patient's age, dosage, or duration of administration.

A typical picture in OCM is diffuse myalgia and muscle weakness. Pelvic girdle involvement is the most common. In some patients, ACM is expressed in the fact that it is difficult for them to remain without a ventilator due to damage to the respiratory muscles.

A number of laboratory tests can help in establishing the diagnosis of ACM. In particular, these are serum CPK, AST, ALT and myoglobin in the urine. Electromyography and muscle biopsy can also help clarify the diagnosis. No analysis, however, is specific. Elevation of serum enzymes is an inconsistent finding in OSM. In our patient, as well as in other described cases, the level of CPK, AST and ALT was increased. However, Askari et al. not all patients with ACM showed an increase in CPK. A more consistent feature of ACM in their patients was elevated urinary creatinine excretion. Electromyography may be normal, often a reduced amplitude of the muscle action potential is found with a preserved speed of conduction of sensory and motor impulses.

Biopsy of muscle tissue in OSM usually shows diffuse necrosis of type 1 and type 2 fibers; however, often a biopsy is not helpful in establishing the diagnosis.

Currently, there are no recommendations for steroid doses that would reduce the likelihood of developing myopathy. Our patient took methylprednisolone twice: 24 mg and 20 mg. A similar case has been described with 40 mg of prednisolone. We were not able to find in the literature descriptions of cases of ACM development when taking prednisolone at a lower dosage.

There is no specific treatment for steroid myopathy. The literature mostly describes cases where myopathy resolves on its own without any intervention upon discontinuation of steroid therapy.

Conclusion

Steroids, as a class of drugs, are the drugs of choice for a number of diseases. They are prescribed by doctors of almost all specialties. Although ACM occurs very rarely, it should be recognized as early as possible in order to stop glucocorticoids in time.

The patient gave written consent for the publication of his case. A copy of the written consent is with the editor-in-chief of the journal (JOURNAL OF MEDICAL CASE REPORTS).

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11. Hanson P, Dive A, Brucher JM, Bisteau M, Dangoisse M, Deltombe T: Acute corticosteroid myopathy in intensive care patients. Muscle Nerve 1997,

Steroid myopathy (SM) is the occurrence of myopathy symptoms (decrease in muscle mass, tone, and muscle strength) in patients who have massive and/or long-term (chronic; both exogenous [drugs] and endogenous [eg, syndrome/disease) Cushing]) exposure to glucocorticoids (GC).

SM is one of the common causes of walking disorders in the elderly, SM exacerbates respiratory problems in the treatment of GCs in patients with bronchial asthma; long-term use of inhaled GCs is associated with the development of dysphonia due to the formation of myopathic changes in the muscles of the larynx; SM is the cause of some cases of "". Even in the absence of clinically pronounced symptoms of myopathy in patients receiving long-term HA in low doses, histological studies reveal signs of myopathy (an increase in the concentration of glycogen in muscle fibers, combined with inhibition of the activity of the main regulatory enzymes that control the processes of glycogen degradation against the background of chronic exposure to HA). Thus, SM is an important medical problem that requires in-depth study.

note! Practitioners should [ 1 ] be aware of the dangers of long-term courses of oral or parenteral GCs and [ 2 ] to resort to the appointment of hormonal therapy only when the potential therapeutic effect of HA exceeds the risk of developing severe complications of the disease (requiring the use of HA).

The physiological function of corticosteroid hormones is to mobilize the body's resources under stress by inhibiting homeostatic processes. GCs reduce the rate of synthesis and increase the breakdown of muscle proteins, which leads to muscle atrophy. GCs inhibit the transport of amino acids into muscles, block the stimulatory effects of insulin, insulin-like growth factor and amino acids on protein synthesis, and suppress myogenesis by inhibiting myogenin synthesis. In addition, GCs inhibit the production of growth factors that control the increase in muscle mass at the local level. Inhibition of muscle proliferation and differentiation under the influence of HA occurs due to an increase in the production of myostatin in the muscles.

At the same time, different muscle groups have different sensitivity to the adverse effects of GC: most often, atrophic changes develop in muscles containing a large number of fast-twitch fibers - fibers of the 2nd type. In particular, the tibialis muscle or the extensors of the fingers are more susceptible to malnutrition in SM compared to the soleus muscle. These differences are due to the minimum content of type 2 fibers in the soleus muscle. In the study by M. Minetto et al. (2010) after a week of taking dexamethasone by healthy subjects, the speed of conduction along muscle fibers decreased to the greatest extent (by 10.5%) in the biceps muscle of the shoulder, to a slightly lesser extent - in the wide medial muscle (by 10%), and even less - in the wide lateral muscle (by 9%) and, to a lesser extent, in the anterior tibial muscle (by 6%). This trend corresponds to the distribution of type 2 fibers in the listed muscles: 60% of type 2 fibers contain biceps, 50% - wide muscles of the thigh and 30% - anterior tibial muscle.

Acute forms of SM manifest weakness in the proximal muscles of the extremities, myalgia with a concomitant increase in serum creatine phosphokinase (CPK) and creatine in the daily urine (however, it should be remembered that even with severe motor or respiratory disorders, the level of CK in SM may remain normal, so the level of creatine in the daily urine may be a more reliable marker of SM). In the vast majority of these patients, acute muscle injury develops when the dose of GCs is increased during their long-term use. Nevertheless, casuistic cases of acute SM have been described after a single oral administration of GC in relatively small doses (20–24 mg of methylprednisolone). Severe forms of acute SM in patients with status asthmaticus may be accompanied by rhabdomyolysis with an increase in serum CPK, myoglobinuria, and the development of acute renal failure. In typical cases, rhabdomyolysis develops after the use of massive doses of HA in combination with muscle relaxants or other drugs with a myotoxic effect (aminoglycosides, etc.).

read also the article: Creatine Kinase: Neurologist's Handbook(to the website)

It is believed that the most pronounced damage in acute SM develops in the quadriceps femoris. However, rhabdomyolysis can also affect the respiratory muscles due to the pronounced load on this muscle group in status asthmaticus. SM may underlie part of the cases of "resistant" [bronchial] asthma. It should be emphasized that moderate weakness of the respiratory muscles is typical for patients with bronchial asthma receiving GCs both systemically and in the form of inhalations. It should also be noted that in animal experiments, the ability of HA to induce atrophic changes in the diaphragm was demonstrated.

Chronic forms of SM are characterized by a decrease in the level of CPK and myoglobin in the blood serum. Also, in patients receiving GCs (including inhaled GCs) for a long / chronic time (during a year or longer periods), leg muscle weakness is a common complaint. Patients with bronchial asthma who regularly use inhaled GCs often complain of dysphonia and fatigue of the muscles of the larynx during speech (in such patients, the cricothyroid muscle suffers the most and, to a lesser extent, the thyroaritenoid muscle).

Systemic side effects of GC are more pronounced in patients with low body weight. In very obese patients, even long-term use of GCs may not be accompanied by either feelings of weakness in the legs or a change in muscle volume. This trend is logical, since in these cases, HA entering the bloodstream is distributed in body tissues in significantly lower concentrations. Nevertheless, obese patients are not spared from such local effects of GC as respiratory and esophageal candidiasis, dysphonia, etc.

note! It is generally accepted that inhaled GCs are significantly safer than systemic GCs. However, moderate manifestations of SM are equally pronounced both in patients receiving systemic GCs and when using inhaled GCs.

Therapeutic tactics in the development of SM involves a dose reduction or withdrawal of GCs (usually with the development of severe SM). The abolition of GC leads to an improvement in both motor functions and the electrophysiological picture. Regular physical activity can also reduce the myopathic effects of HA. A number of studies have shown significant correlations between vitamin D levels and muscle performance. The adverse catabolic effects of HA are reduced by the intake of amino acid mixtures (particularly leucine and glutamine), which increase muscle protein synthesis.

more about SM in the article "Steroid myopathy" by A.G. Polunina, F.V. Isaev, M.A. Demyanov; Main Military Clinical Hospital of the FSB of Russia, Golitsino; Moscow Scientific and Practical Center for Narcology, Moscow (Journal of Neurology and Psychiatry, No. 10, 2012) [read].

read also article: Muscle damage caused by taking statins (on site) and article: Steroid myopathy (at http://polymyosit.livejournal.com) [read]

© Laesus De Liro

Dear authors of scientific materials that I use in my messages! If you see this as a violation of the “Copyright Law of the Russian Federation” or wish to see the presentation of your material in a different form (or in a different context), then in this case, write to me (at the postal address: [email protected]) and I will immediately eliminate all violations and inaccuracies. But since my blog has no commercial purpose (and basis) [for me personally], but has a purely educational purpose (and, as a rule, always has an active link to the author and his scientific work), so I would be grateful to you for the chance make some exceptions for my messages (against existing legal regulations). Sincerely, Laesus De Liro.

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